Liquid fertilizers are used extensively in agriculture, especially in large acreage farms, to promote growth of crops and to ensure germination of planted seeds. There have been many methods and devices employed to apply the liquid fertilizers to newly seeded ground immediately after seeding or planting has been performed.
A conventional device used for delivering liquid fertilizer to newly seeded areas consists of an apparatus that attaches to, and directly follows, an automated seeding or planting apparatus, which is pulled by a tractor, or the like. One commonly employed device is the "Trail Place.TM." liquid fertilizer delivery system of Hawkins Manufacturing, Inc., of Holdredge, Nebr. The Trail Place.TM. apparatus is adapted to be connected directly behind an automated seeder or planter and consists of a dual-disk (i.e., double-coulter) which creates a furrow up to three inches deep in the soil directly behind areas that have had seed applied thereto by the automated seeding device. The fertilizer dispenser consists of a flexible tube that is attached at one end to a fertilizer reservoir, such as, for example, a holding tank, which is mounted on a platform that is disposed at a position above the double-coulter assembly. The other end of the flexible tube is left open and is placed between the two coulters that make up the double-coulter assembly.
When the Trail Place.TM. device is engaged, it follows directly behind the automated seeder. The double-coulter assembly creates a furrow into which the liquid fertilizer is fed through the flexible tube. The open end of the flexible tube is generally attached to a nozzle and directed to the furrow created by the double-coulter assembly. The liquid fertilizer is not applied under pressure and is fed through the flexible tube by the force of gravity. The only mechanism for controlling fertilizer flow is by mechanical adjustment of the nozzle or by changing nozzle size.
There are numerous disadvantages associated with conventional liquid fertilizer delivery systems such as the Trail Place.TM.. These disadvantages include the inability to accurately regulate and control the flow of fertilizer from the reservoir once the fertilization process begins, because the flow is created by gravity and no external pressure or regulation is applied. Therefore, the amount of fertilizer delivered cannot be easily adjusted, especially during operation, based on the speed of the planter or the amount of seed or gallons/acre of coverage desired. In addition, the furrow created by the double-coulter assembly is often quite wide, which results in a furrow that fails to close itself after the fertilizer has been applied. Thus, seed and fertilizer are not subsequently covered by soil and will tend to dry out. Drying out of seed has serious negative implications related to crop yield and overall cost. Therefore, any advantages realized by applying liquid fertilizer may be negated by problems associated with open furrows. Yet another disadvantage of the above-described conventional liquid fertilizer delivery system is that the double-coulter assembly has a tendency to become fouled or inoperative in moist soil or muddy conditions. This may result in destruction of the seed beds and/or improper application of the liquid fertilizer due to the reduced or improper rotation of the coulters.
One of the most serious disadvantages associated with this conventional liquid fertilizer application system is the inability of the double-coulter assembly to swivel or pivot with respect to the automated seeding or planting apparatus, when following such an apparatus through a turn. This inability to pivot results in destruction of seeded areas caused by the double-coulter assembly crossing over already planted rows. This can significantly reduce the effective seeding area and, thus, the effective yield of the farmed area by eliminating a usable portion of the seedable areas at the ends of the bedding rows.